ML20237J661
| ML20237J661 | |
| Person / Time | |
|---|---|
| Site: | Calvert Cliffs  |
| Issue date: | 06/09/1987 |
| From: | Hewitt N, Lawrence R, Thornton A BALTIMORE GAS & ELECTRIC CO., FACTORY MUTUAL ENGINEERING CORP. |
| To: | |
| Shared Package | |
| ML20237J636 | List: |
| References | |
| NUDOCS 8708260253 | |
| Download: ML20237J661 (8) | |
Text
'
ENCICSURE (1) l To 1
i BALTIMORE GAS AND ELECTRIC COMPANY'S.
1 INSERVICE INSPECTION REPORT FOR CALVERT CLIFFS UNIT 1 ASME BOILER AND PRESSURE VESSEL CODE SECTION XI, FORM NIS-1 i
G708260253 870625 ADOCK0500gi7 PDR G
- r c
l*DATE:'
June'9. 1987 NIS-1 PAGE l'
of 6
NIS-1 FORM NIS-1 OWNER'S DATA REPORT FOR INSERVICE INSPECTIONS (As Required by the Provisions of the ASME Code Rules)
- 1. Owner:
Baltimore Gas and Electric Company P.
O.
Box 1475 Baltimore, MD 21203
- 2. Plant:
Calvert Cliffs Nuclear Power Plant Lusby Post Office Lusby, MD 20657
- 3. Plant Unit:
4.
Owner Certification of Authorization:
il NA
- 5. Commercial Service Date:
6.
National Board Number for Unit:
May 8, 1975 20911
- 7. Components Inspected:
COMPONENT MANUFACTURER MANUFACTURER STATE NATIONAL OR OR OR INSTATJRR OR BOARD APPURTENANCE INSTATIRR SERIAL #
PROVINCE #
NUMBER Reactor Combustion Pressure Engineering CE-67107 14000N 20911 i
Vessel Reactor Combustion Pressure Engineering CE-G7207 14000N 20911 Vessel Closure Head Pressuri:::er Combustion Engineering CE-67602 14000N 20915 Steam Combustion Generator Engineering CE-67504 14000N 20922
- 11 Reactor Combustion Coolant Engineering CONTRACT No.
Pipe 72467
- 12A Reactor Byron Jackson Coolant Pump SN-0439 1
.'DATE:
June 9, 1987 NIS-1 PAGE 2
of 6
NIS-1 7.
Components Inspected (Continued) :
COMPONENT MANUFACTURER MANUFACTURER STATE NATIONAL OR OR OR INSTATTRR OR BOARD APPURTENANCE INSTATTRR SERIAL f PROVINCE #
NUMBER
- 11A RCP Byron Jackson SN-lS-77P108 Motor (Motor)
Flywheel
- 11B RCP Byron Jackson SN-35-77P108 Motor (Motor)
Flywheel Safety Bechtel Injection Piping Main' Steam Bechtel Piping Feedwater Bechtel Piping Pressurizer Bechtel Spray Piping I
8.
Examination Dates:
Aucust 28, 1985 to Januarv 12, 1987 9.
Inspection Interval:
May 8, 1975 to Acril 1, 1987
- 10. Abstract of Examinations:
(Include list of exams and statements concerning status of work required for current interval).
(See Enclosures 2 and 3).
The examinations reported herein constitute the eighth such report of Inservice examination performed at Calvert Cliffs Unit 1, and the fourth and final report within the third 40-monuh period of commercial operation.
The examinations for the first interval as required by the Long-Ters Examina-tion plan for Calvert Cliffs Unit 1,
were performed in accordance with the 1971 Edition of ASME Code Section XI with Addenda through Winter 1971 for the first 40-month period and
)
the 1974 Edition of ASME Code Section XI with Addenda through j
Summer 1975 for the second and third 40-month periods.
Hydrostatic and System Pressure Testing Procedures are available at the plant site for review.
DATE:
June 18, 1987 NIS-1 PAGE 3
of 6
NIS-1 11.
Abstract of Conditions Noted:
(See Enclosures 2 & 3) a.
Eddy current examinations of #11 and #12 Steam Generators revealed signs of steam generator tube degradation.
Results of #11 Stean Generator examinations showed that of the 8,488 tubes examined, 21 were defective (imperfec-
>_ 40% wall loss), 86 were degraded
.(.>
20 % wall i
tions
- loss, but < 40%),
113 had imperfections
(<
20% wall loss), and 574 tubes contained service induced denting in
,q the ninth support plate on the hot leg side.
Inspection
-1 of #12 Steam Generator revealed that of the 8,494 tubes 1
l examined, 11 were defective, 106 were degraded, 119 had imperfections, and 923 tubes contained service induced denting in the ninth support plate on the hot leg side.
b.
Code-allowable laminations were recorded during ultrason-ic testing examinations of 34-MS-1204-12 and 13.
One code-allowable planar indication was recorded during the mechanical ultrasonic testing examination of reactor Vessel weld 9-203.
During the ultrasonic testing i
examination of longitudinal weld 14-SI-1204-4LU, an arc-strike was found outside the examination area and reported.
c.
As part of a Baltimore Gas & Electric initiated program to monitor piping for erosion / corrosion effects, wall thickness readings below design minimum wall
(.95 inches),
as low as
.86 inches, were found immediately l
adjacent to the downstream side of inservice inspection weld no. 34-MS-1205-8.
The thin wall pipe section can be characterized as a band 1/2-inch wide and 24 inches long
&djacent to the butt weld.
The length of this band is 22.5% of the inner pipe surface circumference.
12.
Abstract of Corrective Measures Recommended and Taken*
(See Enclosures 2 & 3) a.
Those tubes found to contain imperfections greater than 40% wall loss were removed from service by plugging each
)
end with a mechanical or welded tube plug.
Additionally, j
six tubes which showed eddy current indications of less j
than 40% nominal wall loss were plugged.
Four of these tubes were conservatively plugged due to degradation at supports, one tube was plugged due to an over expanded j
region above the tube sheet and one tube was plugged j
because a
section containing 20%
indications was removed for metallurgical examination.
i 1
(
DATE:
June 9, 1987 NIS-1 PAGE 4
of 6
NIS-1 b.
All ultrasonic testing indications were evaluated, per ASME Code Section XI 1974 Edition through Summer 1975 Addenda, and found acceptable by Baltimore Gas &
Elec-l tric.
The arc strike was removed by light grinding, and l
following reexamination it was found acceptable and returned to service.
l i
i c.
ASME Code Section XI, Article IWA-3000, " Standards for Examination Evaluations," requires this type of material and weld flaw (type C-F) be evaluated by comparison to the original construction requirements as provided in ANSI B31.1-1967.
This flaw does not meet the original construction requirements for minimum wall thickness of 0.95 inches.
BG&E reviewed the construction radiograph of the affected pipe and a new radiograph was taken.
Examination of the films showed no significant differences between the old and new radiographs.
We believe this condition has existed since construction.
The probable cause was grinding on the edge of the pipe to achieve proper fit-up for welding during construction.
Five other locations on the main steam line were ultra-sonically tested to determine if similar conditions existed.
Pipe wall thicknesses were found to meet the minimum wall thickness criteria.
Due to this flaw not meeting the IWA-3000 requirements of Section XI of the 1974 ASME Code, BG&E submitted let'cers to the Nuclear Regulatory Commission dated December 16 and 19, 1986, that requested the ASME Code requirements be updated for this flaw to the r3quirements of the 1983 ASME Code with Addenda through Summer 1983.
This was requested because Article IWB-3600 of the 1983 edition provides analytical evaluation techniques superior to those prescribed by the 1974 edition, and during this cycle (April 1,.1987) Unit 1 vill be required by 10 CFR
- 50. 55a (g) (4 ) (ii) to update to the 1983 Edition with addenda through Summer 1983 of ASME Code Section XI.
t I
1 l
l.
' DATE:
June 9, 1987 NIS-1 l
PAGE 5
of 6
NIS-1 Since the 1983 edition Article IWB-3610(b) evaluation did not meet the primary stress limits of NB-3000, we requested relief until the next Unit 1 refueling cutage from meeting the hoop stress requirement for this piping.
The basis for the approval of these requests is that (1) the affected pipe retains adequate fracture toughness, (2) a limit load analysis shows sufficient wall thickness i
remains to prevent yielding, (3) the affected pipe will be replaced,
- repaired, or shown to meet the primary stress limits by the end of the next refueling
- outage, and (4) the affected pipe is an isolated case.
Interim approval of the Main Steam Piping Flaw was granted by NRC
-l letter dated December 19, 1986.
- 13. NAMES OF INSPECTORS:
R.
W.
Lawrenge N.
S.
Hewitt EMPLOYER CF INSPECTORS: Factory Mutual Encineerine One Bala Plaza Suite 200 t
Bala Cvnwvd, PA 19004 We certify that the Statements made in this report are correct and the examinations and corrective measures taken conform to the rules of the ASME Code,Section XI.
f DATE:
19 8
SIGNED:
~
Baltimore Gas & Electric Company A.
R. Thornton General Supervisor -
Plant & Project Engineering Certificate of Authorization No. EA Expiration Date EA
l
- DATE:
June 9, 1987 NIS-1 l
PAGE 6
of 6
l NIS-1 1
l CERTIFICATE OF INSERVICE INSPECTION i
1 1
I, the undersigned, holding a valid commission issued by the National Board of Boiler and Pressure Vessel Inspectors and/or the State or Province of Maryland and er,loyed by Arkvricht-l Mutual Insurance comeany have inspected the components described in this Owner's Data Report during the period August 28, 1985 to January 12, 1987, and state that to the best of my knowledge and belief, the owner has performed examinations and taken corrective l
measures described in this owner's Data Report in accordance with the requirements of the ASME Code,Section XI.
.1 By signing this certificate neither the Inspector nor his employer makes any warranty, expressed or implied, concerning the examinations and corrective measures described in this owner's j
Data Report.
Furthermore, neither the Inspector nor his employer l
l shall be liable in any manner for any personal injury or property
)
damage or a loss of any kind arising from or connected with this inspection.
DATE:
uM //
19 67, 1
1[d h4 %
INSPECTOR SIGNATURE FACTORY MUTUAL SYSTEM 1
COMMISSION:
NB d 22 0 MD 6 Y7 National Board State Province and No.
a i
c, i
i
~!
ENCLOSURE (2)
.TO BALTIMORE GAS AND ELECTRIC COMPANY'S INSERVICE INSPECTION REPORT
-1 FOR CALVERT CLIFFS UNIT 1
{
1986 INSERVICE EXAMINATION OF SELECTED CLASS 1 AND CLASS 2 COMPONENTS AND SYSTEMS VOLUMES 1 THROUGH 5
l
~.
ENCLOSURE (3)
.i TO BALTIMORE GAS AND ELECTRIC COMPANY'S j
INSERVICE INSPECTION REPORT FOR CALVERT CLIFFS. UNIT 1 t
i STEAM GENERATOR #11 AND #12 EDDY CURRENT TESTING FINAL REPORT OCTOBER / NOVEMBER 1986 l
u_______________________.____._________
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